Treatment of textile materials



Patented July UNITED STATES TREATMENT OF TEXTILE MATERIALS Ernest William Kirk and George Holland Ellis, Spondon, near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware No Drawing.

Application May 26, 1934, Serial No. 727,736. In Great Britain June '9, 1933 1 Claim. (Cl. 85)

This invention relates to the colouration of textile materials and more particularly to the colouration of textile materials by methods involving the formation of difiicultly soluble azo 5 dyes thereon from suitable components. 7

The formation of dimcultly soluble azo dyestuffs on textile materials from diazo compounds and phenolic coupling components, especially the arylamides of 2:3-oxynaphthoicacid, consti- 10 tutes a very valuable method for colouring the said materials. As usually practised, the material is impregnated with the coupling component and the latter then caused to couple with a diazo compound. In the case of cotton, regenerated cellulose, or other cellulose material, it

is the usual practice to impregnate the material with the coupling component and then to treat with a solution of a diazo compound. In the case of some materials, however, and particularly in the case of cellulose acetate or other cellulose ester or ether materials, it is often found more convenient to diazotize the diazo component on the material and thereafter to apply the coupling component or, alternatively,

to apply both the diazo component and the coupling component to the material either together or separately and thereafter subject the material to treatment to effect diazotization and coupling. In the case of cellulosic materials, for

example cotton, the impregnation of the material with'the coupling component is easily effected from alkaline solutions, which may readily be obtained with the aid of several equivalents of caustic alkali to each squivalent of coupling component. From such solutions the components are readily absorbed by the cotton, which is not damaged by the alkali, even when the latter is present in relatively high concentrations. In the case of cellulose ester mate- 40 rials, however, if caustic alkali is used in proportions sufficient to ensure in all cases the solution of the coupling component, there is grave danger of saponifying the ester under the conditions of temperature, concentration, etc., such as are usually employed in dyeing operations of the character in question. It is therefore necessary to restrict the proportion of alkali in the impregnating medium if saponiflcation is to be avoided.

These considerations apply generally to coupling components which require alkali to effect solution in water, for example aromatic hydroxy compounds, e. g. the above-mentioned arylamidesof 2:3-oxynaphthoic acid and also coupling compounds containing the grouping clnco-,

e. g. arylamides of aceto-acetic acid. All these coupling components which, at least in the enol form, containing a hydroxy group, are hereinafter referred to as enolic coupling components.

We have observed that when applying enolic coupling components to cellulose ester materials from baths made with such small proportions of 6 alkalies as to avoid material saponiflcation of the ester, small variations in the alkalinity of the bath have a very marked effect upon the affinity of the coupling component for the ester. In consequence, it is advantageous to control the 10 degree of alkalinity within very narrow limits to obtain uniform and consistent results, and in particular if the full colour value of the coupling component is to be utilized. This is particularly the case with coupling components such 15 as the arylamides of 2:3-oxynaphthoic acids, which are not readily maintained in solution, colloidal or otherwise, except under rather strongly alkaline conditions.

We have now found that in the impregnation 20 of cellulose ester materials with enolic coupling components from alkaline media, the addition of a sugar to the alkaline solutions of the cou-- pling components is of great benefit. The sugar, we have found, enables a greater proportion of 25 alkali to be employed in preparing the impregnation medium than is otherwise permissible, if material saponiflcation of the ester is to be avoided. In particular the addition of the sugar enables the proportion of alkali employed to be 30 that most advantageous from the point of view of causing the absorption of the coupling component to be as uniform and complete as possible, while yet avoiding saponification.

The new process of impregnating cellulose ester 35 materials with an enolic coupling component consists essentially in applying to the material a preparation containing the constituents of acomposition obtainable by adding a sugar to an alkaline solution of the enolic coupling component. Preparations containing the said constituents are included in the scope of the invention. i

By working according to the new process, it is thus possible to secure even colouration and 45 effective utilization of the colour value of the coupling component, while at the same time avoiding a saponification of the material. Moreover, in the presence of the sugar the proportion of alkali requisite to secure these results 50 is by no means critical, a very great advantage in practice.

The utility of the new process is not, however, restricted to the colouration of cellulose ester materials, as it may be applied to colouring of 5 other materials, especially such as absorb enolic coupling components to best advantage from media prepared with greater proportions of alkali than can be otherwise tolerated if damage of the materials is to be avoided.

7 due to its bun'ering action, that is its tendency to render the alkalinity of aqueous media no longer completely dependent on the proportion of alkali employed. We have indeed found that the sugar may be replaced by other buffering agents. As examples oi such other agents may be mentioned polyhydric alcohols, for example mannitol and also substances of weakly acidic character, ior example the" amino acids, especially the aliphatic amino acids, and the dior poly-peptides in which two or more amino acid residues are united, as for example in glycyl-glycine. Suitable amino acids or dior poly-peptides are, for example, those readily obtainable by the acid or alkaline hydrolysis of proteins. If desired, crude hydrolysis products may be employed, for example the crude products obtainable by hydrolyzingv wool or like protein material with aqueous alkali. Again weak inorganic acids may be employed, for example boric acid. Weak dior poly-basic acids are advantageous. There may be employed in general neutral to weakly acid substances which are capable of forming salts with alkalies.

Extremely satisfactory results may, however, be obtained with sugars, and it is preferred to use these bodies. Various sugars may be used, for example cane sugar or other dioses or polyoses. Particularly good results may, however, be obtained by the use of reducing sugars, for example dextrose, laevulose, galactose, or other monoses, or crude products containing these reducing sugars, for example the mixture of glucose and laevulose obtainable by hydrolyzing cane sugar or a crude sugar-containing mixture obtainable by hydrolysis of wood.

The reducing sugars are of especially great advantage when it is required to apply the diazo component simultaneously with the coupling component, which method, as explained above, is frequently practiced in connection with the colouration of cellulose ester materials. The reducing sugar has the very valuable property of restricting the oxidation of the diazo component, a matter of particular importance when the diazo component is a body which is comparatively readily oxidized, for example amino-diphenylamine derivatives, e. g. 4:4'-diamino-diphenylamine. The latter base, in particular, is readily oxidized by the air and in the absence of any precaution to prevent oxidation may become so seriously oxidized when dyeing on a winch machine or other machine in which the air has free access to the materials, as to render the resulting dyeings substantially useless. If desired, the sugar or other buffering agent may be employed in conjunction with a reducing agent and as an example of such a reducing agent, mention may be made of phenyl hydrazine sulphonic acid.

The proportion of alkali employedin preparing the impregnation liquors containing the enolic coupling components may vary within comparatively wide limits, for as explained above, the presence of the sugar or other bufiering agent tends to render the alkalinity of the bath no longer completely dependent on the proportion of alkali employed. For example, caustic alkali sufllcient for complete salt formation with the coupling component may be employed. Particularly good results have, however, been obtained by the employment of caustic alkali in the proportion of about two equivalents per equivalent of a mono-2:3-oxy-naphthoyl aromatic amine, for example 2:3-oxy-naphthoic acid anilide. In the case 01! coupling components containing two or more oxy-naphthoic acid amide groups, proportionately greater quantities of alkali should be employed. Similar considerations apply in connection with other coupling components, that is to say the quantity 0! alkali may advantageously be about that required for complete salt formation with the coupling component.

The proportion 0! sugar or other buffering agent employed is notcritical but should preferably be such as to contain a suflicient proportion of hydroxy, carboxylic or other groups capable oi. forming salts with alkali metals, to combine with the alkali employed. In practice very good results have been obtained by the employment of glucose or other reducing sugar in about twice the weight of the caustic alkali used for effecting solution of the coupling component.

For application to textile materials, the solutions oi! the coupling components may be in the form of either freely fluid liquids for application by bath methods, or in the form of thickened preparations suitable for application by padding, printing or other method of mechanical impregnation. The impregnation baths or padding or printing liquors are very readily prepared simply by dissolving the coupling component with the requisite amount of caustic alkali, for example caustic soda, in the necessary amount of water and then adding the glucose or other buflering agent thereto. If the diazo component is to be applied simultaneously with the coupling component, as is conveniently the case when dyeing cellulose ester materials, it may be dispersed with the aid of Turkey red oil or other dispersing agent and mixed with the solution or the coupling component. Alter the impregnation of the material with the coupling component, the materials are subsequently treated with a solution of the diazo compound or the diazo component. or, where the diazo and coupling components have been applied to the materials, the latter may be treated so as to effect diazotization and coupling. In the case or a cellulose ester material impregnated with both diazo andcoupling components, the material may be treated with an acidified nitrite solution until diazotization is complete and thereafter'subjected to a hot soaping treament in order to complete the coupling.

A wide range of enolic coupling components may be applied to textile materials by the new process. The latter is, however, of particular advantage in connection with the application of coupling components which are diilicult to obtain in the form of true or colloidal solutions. Examples oi! such components are the arylamides of 2:3- and other oxynaphthoic acids and arylamides of other hydroxy carboxylic acids, for example those of the benzene or carbazole series. Again, the invention is of value in connection with the application of p-keto acidyl derivatives of aromatic amines and especially the di-p-keto acidyl derivatives of aromatic diamines, as exemplitled for instance by the diaceto-acetyl derivative oi. ortho-tolidine, commonly known as naphthol AS/G. Still other coupling components may, however, be applied by the new process, for example p-naphthol, or coupling components generally containing hydroxyl and acidylamino groups, for example the 2-acidylamino-3naphthols or the 1-acidylamino-7-naphthols.

In the case of cellulose ester or ether materials, the absorption of the enolic coupling components and/or any diazo component applied simultaneously therewith, may be facilitated by incorporating swelling agents in the baths, padding amass liquors or printing pastes employed, or if desired the materials may be pretreatedwith swelling agents. Alcohol is a particularly suitable agent for this purpose, though other swelling agents may be employed, if desired.

As indicated previously, the invention is of special value in connection with the colouration of cellulose acetate or other cellulose ester materials. As examples of such materials mention may be made, in addition to cellulose acetate, of cellulose formate, propionate or butyrate or mixed esters of cellulose, for example cellulose acetate-butyrate or nitroacetate or materials obtainable by treating cellulose with esterifying agents, while retaining its fibrous form, for example the products obtainable by treating alkali cellulose with paratoluene sulphonic chloride, benzoyl chloride or other acid halides. Other materials may, however, also be coloured by the new process, for example ethyl or benzyl cellulose or other cellulose ethers. Again, animal fibres are advantageously coloured by the new method, for example wool or natural silk, or; if desired, mixed materials containing for instance one or more of the foregoing esters or ethers of cellulose or an animal fibre in conjunction with cotton, regenerated cellulose or other cellulosic fibre. In general, in the case of such a mixed material, the cellulosic component will be left substantially uncoloured under the conditions of alkalinity most suitable for effecting the coloration of a cellulose ester or an animal fibre.

The following examples illustrate the invention but it is to be understood that they do not limit it in any way:

Exsmnn 1 To dye a deep crimson shade, fast to washing, on 10 kilos of yarn 100 grams of 5-nitro-2-aminoanisole are dispersed by heating with 300 grams of Turkey red oil. 200 grams of 2'-oxy-3'-naphthoyl-p-naphthylamine are dissolved with 400 grams of Turkey red oil and50 grams of caustic soda in about 10 litres of hot water. of 100 grams of glucose and the whole of these solutions sieved into a dyebath of 300 litres set at 30 C. The previously well scoured yarn is entered, turned for A hour, and the temperature slowly raised over A an hour to C. and kept at this for one hour further. The yarn is then lifted and rinsed; and diazotized by working for /2 an hour in a cold bath prepared with 4 grams of sodium nitrite and 8 grams of glacial acetic acid per litre. The yarn is again lifted and rinsed, and turned for a A hour in a cold bath containing gram per litre soda ash, lifted and entered into a bath containing 1 gram per litre good textile soap, and turned cold for V hour. The temperature is then slowly raised to C. and the yarn turned at this temperature until the correct shade is obtained, then lifted, rinsed. and dried or otherwise treated as requisite.

Exmnr 2 To-dye a full lemon-yellow shade on 10 kilos of cellulose acetate knit fabric grams of 2:5 dichlorsniline, grams of diacetoacetyl-orthotolidine, 100 grams caustic soda, and 500 grams of Turkey red oil, are heated To this is added a solution a soft water at50" C. in which 400 grams of corn syrup" has previously been dissolved. The scoured fabric is entered and worked for an hour at 50 C. and the temperature gradually raised to 75 C. and kept at this for an hour. The 5 bath is then dropped, and the fabric rinsed oil, and diazotized by working for an hour cold in a fresh bath prepared with 4 grams per litre sodium nitrite and 5 cos. per litre formic acid. The diazotization bath is dropped, and the fabric 10 thoroughly rinsed, and soaped up to shade and finished as in Example 1 above.

Exsmrnn 3 r0 dye a fast blue shade on 10 kilos of natural 15 silk yarn 200 grams of 2'-oxy-3'-naphthoyl-ortho-toluidine, 50 grams of caustic soda and 200 grams of Turkey red oil are heated with 10 litres of water until solution is complete. This solution is then filtered into a dyebath of 300 litres of soft water at 50 C. containing grams of glucose and the silk yarn entered and turned for V an hour at this temperature, and the temperature then gradually raised over a further /z an hour to 95 C. and kept at this for a further hour. The yarn is then cooled off in the bath to 50 C. and then rinsed and entered into coupling bath at 70 C. containing a sufliciency of the diazo compound from 4'-methoxy4-aminodiphenylamine and also a suitable protective colloid. When coupling is complete, the yarn is lifted, thoroughly rinsed, and soaped to shade at 95-98 C. then again lifted, rinsed, and dried, or otherwise treated as requisite.

EXAMPLE 4 To due 10 kilos of a cotton/cellulose acetate woven fabric a fast blue shade on the cotton and a fast golden brown shade on the cellulose acetate temperature is gradually raised to 75-80 C. and

kept at this for 2-3 hours. The fabric is then rinsed, and diazotized at 30 C. for an hour in a bath prepared with 5 grams per litre sodium nitrite and 10 cos. per litre glacial acetic acid. The fabric is again rinsed and soaped at 75 C. for an hour, rinsed and dried or otherwise so treated as desired.

What we claim and desire to secure by Letters Patent 18:?-

Process for impregnating cellulose acetate materials with a diazotizable amine and an enolic g5 coupling component, which comprises immersing the materials in an aqueous bath containing a diazotizable amine and the constituents of a composition obtainable by adding a reducing sugar to a solution of an enolic coupling component in 70 aqueous caustic alkali.

ERNEST WILLIAM ma.

GEORGE HOLLAND ELLIS. 

